Brown University biologists studied tomato varieties that produce fruit in
exceptionally hot growing seasons and found what makes some types more heat
tolerant, yielding insights that could help tomatoes adapt to climate
change, as rising temperatures are predicted future crop yields.



The researchers identified the growth cycle phase when tomatoes are most
vulnerable to extreme heat, and the molecular mechanisms that make the
plants more heat tolerant. Study author Sorel V. Yimga Ouonkap, a research
associate in molecular biology, cell biology, and biochemistry at Brown said
they tried to figure out thermoregulation at a molecular and cellular level
to target those in commercial varieties.



Ouonkap focused on the pollen tube growth phase of the plant reproductive
cycle. He studied different tomato plants known for their ability to produce
fruit in exceptionally hot growing seasons, including varieties native to
the Philippines, Russia, and Mexico. With scientists at the University of
Arizona, Ouonkap studied how gene expression changes when tomato pollen is
exposed to high temperatures. The Arizona team found that exposure to high
temperature solely during the pollen tube growth phase limits fruit and seed
production more significantly in tomato plants that were heat sensitive than
those that were heat tolerant.



Ouonkap also found that pollen tubes from the Tamaulipas tomato variety,
known to be heat tolerant, have enhanced growth under high temperatures. His
molecular analysis of the pollen tube in these tomatoes allowed the research
team to identify the mechanisms associated with thermotolerance.



[www.brown.edu]